Novel stabilized capsules have been developed in order to develop a colloid stabilization system including a composite of edible biopolymer with protein. It is thought that when glycoproteins originated from plant peptides have anti-oxidative activity, it is possible to protect a material carried by capsules more stably. Particularly, many attempts have been made to accomplish such stabilization by introducing naturally occurring biopolymers as substitutes for conventional petroleum-derived synthetic polymers.
The present inventors have recognized that capsules including a plant glycoprotein in addition to a polysaccharide and protein can be prepared in a simple and convenient manner and have anti-oxidative activity, and thus significantly increase the stability of a material carried by such capsules. The present invention is based on this recognition.